This invention relates to key blanks and more particularly to bypass keys and methods for using the bypass keys to change locks and to service particular types of door locks without removing the locks from the doors.
Previously in the lock-service industry, it has been necessary for locksmiths to remove entire locks from doors in order to change locks and otherwise to service most of the more widely-used door locks. In some of the currently popular door locks, there are inside keyless lock mechanisms referred to commonly as entry locks. They allow the door to be locked from one side, such as within a building or a room, without a key but require a key for unlocking the door from the opposite side or from outside the room or building. When a key has been lost or stolen, or when there is a new user of a lock, a particular user of the lock may want to prevent others who may have keys to the lock from unlocking or using it. This requires servicing of the lock by changing or replacing the lock cylinder to use a different key.